package org.simantics.processeditor.dialogs;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Stack;

import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.List;
import org.eclipse.swt.widgets.Shell;
import org.simantics.db.Graph;
import org.simantics.db.GraphRequestAdapter;
import org.simantics.db.GraphRequestStatus;
import org.simantics.db.Resource;
import org.simantics.db.Session;
import org.simantics.layer0.utils.EntityFactory;
import org.simantics.layer0.utils.IEntity;
import org.simantics.processeditor.ProcessResource;
import org.simantics.proconf.ui.ProConfUI;
import org.simantics.utils.ErrorLogger;


public class LibraryComponentDialog extends Dialog{ 
	
	 private List typeList;
     private Resource selectedType = null;
     private Session session;
     private String title;
     
     private Resource primaryType;
     private Collection<Resource> requiredTypes = new ArrayList<Resource>();
     private Collection<Resource> filteredTypes = new ArrayList<Resource>();
     
     public LibraryComponentDialog(Shell shell, Session session, Resource primaryType, String title) {
    	 super(shell);
    	 assert(title != null);
    	 this.session = session;
    	 this.title = title;
    	 this.primaryType = primaryType;
     }
     
     
     protected void setFilter(Collection<Resource> filter) {
    	 this.filteredTypes = filter;
     }
     
     protected void setRequired(Collection<Resource> required) {
    	 this.requiredTypes = required;
     }
     
     
     @Override
     protected void configureShell(Shell newShell) {
         
         super.configureShell(newShell);
         newShell.setText(title);
     }

     public Resource getComboValue() {
         return selectedType;
     }
     
     protected Control createDialogArea(Composite parent) {
         Composite composite = (Composite) super.createDialogArea(parent);
         
         Label label = new Label(composite, SWT.WRAP);
         label.setText("Select Component");
         GridData data = new GridData(GridData.GRAB_HORIZONTAL
                 | GridData.GRAB_VERTICAL | GridData.HORIZONTAL_ALIGN_FILL
                 | GridData.VERTICAL_ALIGN_CENTER);
         data.widthHint = convertHorizontalDLUsToPixels(IDialogConstants.MINIMUM_MESSAGE_AREA_WIDTH);
         label.setLayoutData(data);
         label.setFont(parent.getFont());
         // TODO : list populating is done in random order; change to alphabetic
         typeList = new List(composite, SWT.BORDER | SWT.SINGLE | SWT.READ_ONLY | SWT.V_SCROLL);
         typeList.setLayoutData(new GridData(GridData.GRAB_HORIZONTAL | GridData.HORIZONTAL_ALIGN_FILL));
         
         typeList.addSelectionListener(new SelectionListener() {
             public void widgetSelected(SelectionEvent e) {
                 String key = typeList.getItem(typeList.getSelectionIndex());
                 selectedType = (Resource) typeList.getData(key);
             }
             public void widgetDefaultSelected(SelectionEvent e) {
             }
         });
         getShell().setText(title + " loading...");
         session.asyncRead(new GraphRequestAdapter() {
         	@Override
         	public GraphRequestStatus perform(Graph g) throws Exception {
         		loadComponents(g);
         		return GraphRequestStatus.transactionComplete();
         	}
         	
         	@Override
         	public void requestCompleted(GraphRequestStatus status) {
         		getDialogArea().getDisplay().asyncExec(new Runnable() {
         			@Override
         			public void run() {
         				getShell().setText(title);
         				if (selectedType == null) {
         	                typeList.select(0);
         	                selectedType = (Resource)typeList.getData(typeList.getItem(0));
         	            }
         			}
         			
         		});
         	}
         });

         GridData data2 = new GridData(GridData.GRAB_HORIZONTAL
                 | GridData.GRAB_VERTICAL | GridData.HORIZONTAL_ALIGN_FILL
                 | GridData.VERTICAL_ALIGN_FILL);
         data2.widthHint = convertHorizontalDLUsToPixels(IDialogConstants.MINIMUM_MESSAGE_AREA_WIDTH);
         data2.heightHint = 200;
         typeList.setLayoutData(data2);
         typeList.setFont(parent.getFont());
         
         typeList.showSelection();
         
         applyDialogFont(composite);
         return composite;
     }
     
     private void loadComponents(Graph g) {
 		Resource projectResource = ProConfUI.getProject().getResource();
 		Stack<Resource> handling = new Stack<Resource>();
 		handling.push(projectResource);
 		while (!handling.isEmpty()) {
 			final Resource node = handling.pop();
 			if (g.isInstanceOf(node,primaryType)) {
 				IEntity equipment = EntityFactory.create(g, node);
 				Collection<IEntity> graphics = equipment
 						.getRelatedObjects(ProcessResource.plant3Dresource.HasGraphics);
 				if (graphics.size() != 1) {
 					ErrorLogger.defaultLogError("Equipment "
 							+ equipment.getName() + " has " + graphics.size()
 							+ " + graphical representation!", null);
 				} else {
 					boolean add = true;
 					for (Resource r : requiredTypes) {
 						if (!equipment.isInstanceOf(r)) {
 							add = false;
 							break;
 						}
 					}
 					if (add) {
 						for (Resource r : filteredTypes) {
 							if (equipment.isInstanceOf(r)) {
 								add = false;
 								break;
 							}
 						}
 					}
 					if (add) {
 						final String name = equipment.getName();
 						getDialogArea().getDisplay().asyncExec(new Runnable() {
 							public void run() {
 								// List won't work with two ore more same names.
 								if (typeList.getData(name)!= null) {
 									String n = new String(name);
 									int i = 1;
 									while (true) {
 										n = name +"("+i+")";
 										if (typeList.getData(n)== null) {
 											typeList.add(n);
 		 									typeList.setData(n, node);
 		 									break;
 										}
 									}
 								} else {
 									typeList.add(name);
 									typeList.setData(name, node);
 								}
 							}
 						});
 					}
 				}
 			} else {
 				handling.addAll(g.getObjects(node,
 						ProcessResource.builtins.ConsistsOf));
 			}

 		}
 		
 	}
	

}